Wrapped header pipes. Good idea?

[bigbikerrick]

Hello folks, When removing tupperware for cleaning, I noticed the PO had wrapped all the header pipes in that fiberglass insulating header wrap. I have never been a fan of that stuff where it shows on a bike. On the ST, its hidden by the bodywork. I imagine it was done in an attempt to help aleviate the ST's heat issues. Is it a good idea , and should I leave it be, or should I remove it? I have heard that it can exacerbate corrosion of the pipes, but I think the ST exhaust is stainless steel.
What are the groups thoughts?
Rick.

 

[Oldbikefixr]

I never cared for the stuff either. Usually used to cover up rusted/marginal header pipes as it's cheaper than replacement parts. The fact that it collects moisture and retains it against the pipes after they cool just bothers me.

 

[klaproth]

Larry ( Igofar) has said that it will rot the pipes, but I have not heard of any actual pipes corroded by it. But, then again, I have not heard of many folks here using it either, on the stainless pipes. I'd sure like to know if it makes the bike more rideable ( cooler).

 

[SMSW]

I've not read any info that convinced me that it does any good. The occasional guy saying it made a huge difference does not make any more impact on me than those that tout a magnet on the fuel supply giving them 50% more mpg. And it is obvious that the wrapping will trap moisture and corrode steel exhaust headers faster than unwrapped pipes. In the end its your choice.

 

[Bmacleod]

The general thought is that header wrap is bad for the pipes. BUT... there are many reports of ST1300's being unbearably hot. Some have this issue and some dont. Reading the different stories of overly hot bikes, I have often thought that if I had one of these and I couldnt make it bearable, I would try wrapping the headers, accepting that I may have to replace them. If you arent a fan, I would try the bike for a bit and see how it is for heat then remove it and see if it really had much effect. You will get differing opinions on whether or not it works and you'll never know for sure until you try it and because you already have it you are in a good position to try it at no cost

 

[Igofar]

Header wrap will trap moisture and rust out the header pipes over time.
If your bike is running very hot, using header wrap may shield the rider from feeling heat, however, it also will keep more heat in the engine, causing it to run hotter.
If your having heat issues, a proper state of tune will help more than tin foil or header wrap on things.

 

[Upt' North]

Exhaust wrap has always seemed like witchcraft to me but, some say it helps improve power and reduce engine heat loss. So you’ll also see a reduction in temperatures around the exhaust as well as more horsepower.
But? Is it true?
They claim that these benefits are the result of increased engine efficiency. You’ll get more horsepower because the wrap will keep exhaust heat in the headers instead of dissipating to other areas of your engine. So when
heat is contained within the exhaust system it will improve the flow of exhaust gasses throughout the entire system. But will it?

Now who claims this nonsense, or is it?

In a dyno test by Hot Rod Magazine they found exhaust wrap significantly reduced engine temperatures. On unwrapped headers, the temperature near the cylinder head was 1,156 degrees Fahrenheit. After the wrap was applied, the temperature dropped to 972 degrees Fahrenheit. Witchcraft? Well unless they had a faulty temp sensor or lied it did reduce the temperature NEAR to the cylinder head (?).

I'm with Larry maybe you should make sure the bike is right before applying the tape or in your case after. I have no idea how the wrap would cause corrosion on stainless, only time will tell. The quality of the wrap can vary greatly as can its application.
Upt'North.

 

[Larry Fine]

Seems to me that, by the time the exhaust gasses are in the headers, it's too late to extract any more crankshaft power.

 

[Shawn K]

Yeah, that. ^^

 

[bigbikerrick]

Hello folks, When removing tupperware for cleaning, I noticed the PO had wrapped all the header pipes in that fiberglass insulating header wrap. I have never been a fan of that stuff where it shows on a bike. On the ST, its hidden by the bodywork. I imagine it was done in an attempt to help aleviate the ST's heat issues. Is it a good idea , and should I leave it be, or should I remove it? I have heard that it can exacerbate corrosion of the pipes, but I think the ST exhaust is stainless steel.
What are the groups thoughts?
Rick.

Thanks for all the replies, Folks. Maybe the stuff does work to reduce heat to the rider. The temps here in Southern Arizona have been over 100F every day, and I have not felt excessive heat coming off the bike, except for the lower rear edge of the fuel tank, which feels pretty warm after a highway ride. The previous owner informed me that he did not install it.The wrap was installed by the Hannigan dealer, when they installed the sidecar, as the subframe runs pretty close to the headers below the engine, so I may be better off to leave it in place.
Thanks alot
Rick.

 

[beemerphile]

Seems to me that, by the time the exhaust gasses are in the headers, it's too late to extract any more crankshaft power.

The theory is that it increases the velocity and thus increases exhaust gas scavenging. So there is at least a theoretical benefit to that. I have used wrap many times on pipes that were contained within fairings. I wasn't doing it for engine performance or cool looks. On early BMW R1100RT's the fairing lowers would actually droop from the heat after prolonged idling (traffic jams, etc.). Shoot an exhaust pipe at operating temperature with a heat gun and you will get about 1100 degrees F. Keeping that heat out of the inside of the fairing has to help with local heating. I am planning to wrap the pipes on two bikes in the current queue... A K1100RS and an ST1100. There are a couple of keys to to minimizing the damage. First, I always ceramic coat the pipes inside and out prior to wrapping - even stainless pipes, because they are usually inexpensive rustable 304 grade. Secondly, I make sure that there is no double wrap on the pipes (this means reducing the overlap). Thirdly, I buy the standard thinner wrap instead of the extra super-duper high insulation kind. When you do this, any moisture is expelled by the heat during operation. If the wrap can trap the moisture, it is either spec'ed or installed incorrectly. I think that moisture, as a problem, is over-stated with regards to pipes contained beneath fairings. What DOES end up hotter is the exit gas temperature. I have a friend who melted his left rear turn signal with the hotter exhaust.

Another thing that takes a lot of heat out of the bike (only on fuel injected bikes) is a fuel cooler. The fuel that is bypassed from the end of the fuel rail for pressure control ends up being a continuous heating loop that can eventually boil the fuel in the tank. Most people think that the heat in the tank is conducted from the hot engine below. Some of it is, but a lot of it is from the fuel recirculation loop. In those cases, as I plan on my K1100RS, I route the fuel from the regulator to a radiator in front of the engine radiator and then back to tank.

 

[ST11Nut]

Great information!

Thanks Lee

 

[bigbikerrick]

The theory is that it increases the velocity and thus increases exhaust gas scavenging. So there is at least a theoretical benefit to that. I have used wrap many times on pipes that were contained within fairings. I wasn't doing it for engine performance or cool looks. On early BMW R1100RT's the fairing lowers would actually droop from the heat after prolonged idling (traffic jams, etc.). Shoot an exhaust pipe at operating temperature with a heat gun and you will get about 1100 degrees F. Keeping that heat out of the inside of the fairing has to help with local heating. I am planning to wrap the pipes on two bikes in the current queue... A K1100RS and an ST1100. There are a couple of keys to to minimizing the damage. First, I always ceramic coat the pipes inside and out prior to wrapping - even stainless pipes, because they are usually inexpensive rustable 304 grade. Secondly, I make sure that there is no double wrap on the pipes (this means reducing the overlap). Thirdly, I buy the standard thinner wrap instead of the extra super-duper high insulation kind. When you do this, any moisture is expelled by the heat during operation. If the wrap can trap the moisture, it is either spec'ed or installed incorrectly. I think that moisture, as a problem, is over-stated with regards to pipes contained beneath fairings. What DOES end up hotter is the exit gas temperature. I have a friend who melted his left rear turn signal with the hotter exhaust.

Another thing that takes a lot of heat out of the bike (only on fuel injected bikes) is a fuel cooler. The fuel that is bypassed from the end of the fuel rail for pressure control ends up being a continuous heating loop that can eventually boil the fuel in the tank. Most people think that the heat in the tank is conducted from the hot engine below. Some of it is, but a lot of it is from the fuel recirculation loop. In those cases, as I plan on my K1100RS, I route the fuel from the regulator to a radiator in from of the engine radiator and then back to tank.

Thanks for the informative response, Lee. It all makes perfect sense to me. Yes its amazing how hot the bottom rear of the ST 1300 upper fuel tank gets when its over 100 out here in Arizona. The fuel cooler sounds like an excellent idea. The drag racers sure swear by them!
Rick.

 

[Bmacleod]

The theory is that it increases the velocity and thus increases exhaust gas scavenging. So there is at least a theoretical benefit to that. I have used wrap many times on pipes that were contained within fairings. I wasn't doing it for engine performance or cool looks. On early BMW R1100RT's the fairing lowers would actually droop from the heat after prolonged idling (traffic jams, etc.). Shoot an exhaust pipe at operating temperature with a heat gun and you will get about 1100 degrees F. Keeping that heat out of the inside of the fairing has to help with local heating. I am planning to wrap the pipes on two bikes in the current queue... A K1100RS and an ST1100. There are a couple of keys to to minimizing the damage. First, I always ceramic coat the pipes inside and out prior to wrapping - even stainless pipes, because they are usually inexpensive rustable 304 grade. Secondly, I make sure that there is no double wrap on the pipes (this means reducing the overlap). Thirdly, I buy the standard thinner wrap instead of the extra super-duper high insulation kind. When you do this, any moisture is expelled by the heat during operation. If the wrap can trap the moisture, it is either spec'ed or installed incorrectly. I think that moisture, as a problem, is over-stated with regards to pipes contained beneath fairings. What DOES end up hotter is the exit gas temperature. I have a friend who melted his left rear turn signal with the hotter exhaust.

Another thing that takes a lot of heat out of the bike (only on fuel injected bikes) is a fuel cooler. The fuel that is bypassed from the end of the fuel rail for pressure control ends up being a continuous heating loop that can eventually boil the fuel in the tank. Most people think that the heat in the tank is conducted from the hot engine below. Some of it is, but a lot of it is from the fuel recirculation loop. In those cases, as I plan on my K1100RS, I route the fuel from the regulator to a radiator in from of the engine radiator and then back to tank.

This is really good information. Out of the many pipes you have wrapped, have you had any issues with corrosion or cracking?

 

[beemerphile]

This is really good information. Out of the many pipes you have wrapped, have you had any issues with corrosion or cracking?

No, I have not. Some people seem to think that if something is worth doing, then it is worth over-doing. This is one of the many cases where that is just not true. I would wager that very few people do the ceramic undercoat that I do though. I can't say how it would turn out without it. Most likely it would be fine if you use standard thickness wrap and as little overlap (25% or less) as possible. I've done many for R1100RT and R1150RT owners. The K1100RS and the ST1100 that I am planning to wrap are my first for those bikes.

EDITED TO ADD:

Here is the ceramic coated stainless steel header prepped for the K1100RS

before coating, it had a finish that matched the silencer...

 

[Kevin_56]

because they are usually inexpensive rustable 304 grade

I am sorry but all 300 series SS is NON magnetic and will not "rust" easily if at all. 400 series SS is magnetic and the iron in this series will show rust. Do not believe me, take a magnet to these 2 types and you will feel the proof. Her is a nice read on 300 series SS

 

[mlheck]

My pipes have been wrapped for about 10 years and they are not coated. The fact that they are Stainless Steel helps I'm sure. No rust that I'm aware off, but I'm not going to unwrap them to check. No exhaust noise or rust mark's on the garage floor though.

I can't say that it is the golden key for the heat, but it does help. While some may say that the heat can be fixed by a proper tune, I've made all of the adjustments available and the bike still runs hot. I've learned after being on this forum for many years that the '05 bikes are some of the warmer bikes.

 

[NMSTrider]

I think it was last year when a thread of wrapping pipes came through here and rusting was a concern of some. I had done it in 2012 to relieve the heat on my ankles and shins and it is without a doubt the best thing I have done for the problem. The thought of rusting pipes got my attention and I went straight away to my bike and pulled back the wrap on one header. There was no sign of rust after 7 years and nearly 50,000 miles. Perhaps it helps to live in New Mexico at 10% relative humidity and 14 inches annual rain.

 

[beemerphile]

I am sorry but all 300 series SS is NON magnetic and will not "rust" easily if at all. 400 series SS is magnetic and the iron in this series will show rust. Do not believe me, take a magnet to these 2 types and you will feel the proof. Her is a nice read on 300 series SS

You may be a better metallurgist than I am, but from my experience I will buy "not easily" and disagree with "not at all". I don't recall saying that 304 was not austenitic, only that it could rust. This is especially true at the welds unless the metal is passivated after welding. Any stainless has significantly higher resistance to rust because of the chromium content, but is not impervious.

https://forums.swedespeed.com/showthread.php?327521-Have-your-stainless-steel-muffler-started-to-rust

https://stainlesssteelfabricatorsperth.com/the-ultimate-reasons-as-to-why-stainless-steel-rusts/

many others. the evidence is out there.

 

[SMSW]

A couple of points need to be emphasized. There is usually a whole lot more to so called 'simple things we can do to improve something' as pointed out by @beemerphile. I came to trust MCN's testing protocol but often wonder about other so called impartial tests. Hot Rod Mag is one of them. Of course wrapping some kind of insulation around the exhaust headers will show a lower temp on the header. That's the expected outcome. I wonder what their dyno test showed. @Larry Fine's point that once the exhaust gasses leave the cylinder head they have no effect on the efficiency or hp of an engine is correct, unless the system is tuned for the exhaust pulses to aid extracting exh gasses from the cylinders - the scavenging that Lee mentioned. If the system is properly designed, changing the exhaust gases velocity will probably upset the pulse timing, weakening the engine's output. There are too many variables here to expect significant gains in power and/or efficiency.

Wrapping to slow heat transfer is a whole different animal. Insulating anything from the environment will do exactly this. I can't argue this not having done it.

I keep coming back to Ryan Fortnine's comments about motocycle reviewers. He said none of them is to be trusted. Even MCN tested some bikes, found many faults yet still rated the bike with four or four+ red dots. Adds more reason to believe Ryan - and expand it to include most of those folks out there who test products and publish the results.